Spam Control Considered Harmful

Greg A. Woods woods at
Fri Oct 31 07:43:37 UTC 1997

[ On Wed, October 29, 1997 at 15:12:46 (-0800), Dalvenjah FoxFire wrote: ]
> Subject: Re: Spam Control Considered Harmful
> The only reason I can think of that would stop this would be if a
> user subscribes to earthlink, but uses a UUnet dialin, that customer's
> software would be set up to use the Earthlink SMTP servers.

This should only present a minor complexity.  If the authentication
information can be retrieved from the correct home ISP then there should
be no trouble identifying that ISP and adding the right filter to their

> Keep in mind again I don't yet know much about how this would impact
> router performance..but wouldn't one be able to set up access-lists,
> then, that would allow port-25 connections to a defined list of SMTP
> servers (say, UUnet, MSN, and earthlink SMTP servers), and prohibit
> everything else?

One more filter rule in the existing list for preventing IP spoofing
shouldn't make any significant difference.

> Why aren't they doing this?

Probably because they're not preventing IP spoofing yet either.

							Greg A. Woods

+1 416 443-1734      VE3TCP      <gwoods at>      <robohack!woods>
Planix, Inc. <woods at>; Secrets of the Weird <woods at>

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